Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

You are given a string s consisting of n lowercase Latin letters. Some indices in this string are marked as forbidden.

You want to find a string a such that the value of |a|·f(a) is maximum possible, where f(a) is the number of occurences of a in s such that these occurences end in non-forbidden indices. So, for example, if s is aaaa, a is aa and index 3 is forbidden, then f(a) = 2 because there are three occurences of a in s (starting in indices 1, 2 and 3), but one of them (starting in index 2) ends in a forbidden index.

Calculate the maximum possible value of |a|·f(a) you can get.

Input

The first line contains an integer number n (1 ≤ n ≤ 200000) — the length of s.

The second line contains a string s, consisting of n lowercase Latin letters.

The third line contains a string t, consisting of n characters 0 and 1. If i-th character in t is 1, then i is a forbidden index (otherwise i is not forbidden).